Probing the nature of high‐<i>z</i> short GRB 090426 with its early optical and X‐ray afterglows

Xin, Li‐,Ping,Liang, En‐,Wei,Wei, Jian‐,Yan,Zhang, Bing,Lv, Hou‐,Jun,Zheng, Wei‐,Kang,Urata, Yuji,Im, Myungshin,Wang, Jing,Qiu, Yu‐,Lei,Deng, Jin‐,Song,Huang, Blackwell Publishing Ltd 2011 MONTHLY NOTICES- ROYAL ASTRONOMICAL SOCIETY Vol.410 No.1

<P><B>ABSTRACT</B></P><P>GRB 090426 is a short‐duration burst detected by <I>Swift</I> (<IMG src='/wiley-blackwell_img/equation/MNR_17419_mu1.gif' alt ='inline image'/> s in the observer frame and <IMG src='/wiley-blackwell_img/equation/MNR_17419_mu2.gif' alt ='inline image'/> s in the burst frame at <I>z</I>= 2.609). Its host galaxy properties and some gamma‐ray‐related correlations are analogous to those seen in long‐duration gamma‐ray bursts (GRBs), which are believed to be of a massive star origin (so‐called Type II GRBs). We present the results of its early optical observations with the 0.8‐m Tsinghua University–National Astronomical Observatory of China Telescope (TNT) at Xinglong Observatory and the 1‐m LOAO telescope at Mt Lemmon Optical Astronomy Observatory in Arizona. Our well‐sampled optical afterglow light curve covers from <IMG src='/wiley-blackwell_img/equation/MNR_17419_mu3.gif' alt ='inline image'/> to 10<SUP>4</SUP> s after the GRB trigger. It shows two shallow decay episodes that are likely due to energy injection, which end at <IMG src='/wiley-blackwell_img/equation/MNR_17419_mu4.gif' alt ='inline image'/> and 7100 s, respectively. The decay slopes after the injection phases are consistent with each other (<IMG src='/wiley-blackwell_img/equation/MNR_17419_mu5.gif' alt ='inline image'/>). The X‐ray afterglow light curve appears to trace the optical, although the second energy‐injection phase was missed due to visibility constraints introduced by the <I>Swift</I> orbit. The X‐ray spectral index is <IMG src='/wiley-blackwell_img/equation/MNR_17419_mu6.gif' alt ='inline image'/> without temporal evolution. Its decay slope is consistent with the prediction of the forward shock model. Both X‐ray and optical emission are consistent with being in the same spectral regime above the cooling frequency (<IMG src='/wiley-blackwell_img/equation/MNR_17419_mu7.gif' alt ='inline image'/>). The fact that <IMG src='/wiley-blackwell_img/equation/MNR_17419_mu8.gif' alt ='inline image'/> is below the optical band from the very early epoch of the observation provides a constraint on the burst environment, which is similar to that seen in classical long‐duration GRBs. We therefore suggest that death of a massive star is the possible progenitor of this short burst.</P>

Properties of the planetary caustic perturbation

Chung, Sun‐,Ju,Lee, Chung‐,Uk Blackwell Publishing Ltd 2011 Monthly notices of the Royal Astronomical Society Vol.411 No.1

<P><B>ABSTRACT</B></P><P>Just two of 10 extrasolar planets found by microlensing have been detected by the planetary caustic, despite the higher probability of planet detection relative to the central caustic, which has been responsible for four extrasolar planet detections. This is because the perturbations induced by the planetary caustic are unpredictable, thus making it difficult to carry out strategic observations. However, if future high‐cadence monitoring surveys are conducted, the majority of planetary caustic events including the events by free‐floating planets and wide‐separation planets would be detected. Hence, understanding the planetary caustic perturbations becomes important. In this paper, we investigate in detail the pattern of the planetary caustic perturbations. From this study, we find three properties of the planetary caustic perturbations. First, planetary systems with the same star–planet separation (<I>s</I>) basically produce perturbations of constant strength, regardless of the planet‐to‐star mass ratio (<I>q</I>), but the duration of each perturbation scales with <IMG src='/wiley-blackwell_img/equation/MNR_17664_mu1.gif' alt ='inline image'/>. Secondly, close planetary systems with the same separation produce essentially the same negative perturbations between two triangular‐shaped caustics, regardless of <I>q</I>, but the duration of the perturbations scales with <IMG src='/wiley-blackwell_img/equation/MNR_17664_mu2.gif' alt ='inline image'/>. Thirdly, the positive perturbations for planetary systems with the same mass ratio become stronger as the caustic shrinks with the increasing |log <I>s</I>|, while the negative perturbations become weaker. We estimate the degeneracy in the determination of <I>q</I> that occurs in planetary caustic events. From this, we find that the mass ratio can be more precisely determined as <I>q</I> increases and |log <I>s</I>| decreases. We also find that the degeneracy range of events for which the source star passes close to the planetary caustic is usually very narrow, and thus it would not significantly affect the determination of <I>q</I>.</P>

New light‐travel time models and orbital stability study of the proposed planetary system HU Aquarii

Hinse, T. C.,Lee, J. W.,Goź,dziewski, K.,Haghighipour, N.,Lee, C.‐,U.,Scullion, E. M. Blackwell Publishing Ltd 2012 Monthly notices of the Royal Astronomical Society Vol.420 No.4

<P><B>ABSTRACT</B></P><P>In this work we propose a new orbital architecture for the two proposed circumbinary planets around the polar eclipsing binary HU Aquarii. We base the new two‐planet, light‐travel time model on the result of a Monte Carlo simulation driving a least‐squares Levenberg–Marquardt minimization algorithm on the observed eclipse egress times. Our best‐fitting model with <IMG src='/wiley-blackwell_img/equation/MNR_20283_mu1.gif' alt ='inline image'/> resulted in high final eccentricities for the two companions leading to an unstable orbital configuration. From a large ensemble of initial guesses, we examined the distribution of final eccentricities and semimajor axes for different <IMG src='/wiley-blackwell_img/equation/MNR_20283_mu2.gif' alt ='inline image'/> parameter intervals and encountered qualitatively a second population of best‐fitting parameters. The main characteristic of this population is described by low‐eccentric orbits favouring long‐term orbital stability of the system. We present our best‐fitting model candidate for the proposed two‐planet system and demonstrate orbital stability over one million years using numerical integrations.</P>

Rescue of epithelial HCO₃⁻ secretion in murine intestine by apical membrane expression of the cystic fibrosis transmembrane conductance regulator mutant F508del

Xiao, Fang,Li, Junhua,Singh, Anurag Kumar,Riederer, Brigitte,Wang, Jiang,Sultan, Ayesha,Park, Henry,Lee, Min Goo,Lamprecht, Georg,Scholte, Bob J.,De Jonge, Hugo R.,Seidler, Ursula Blackwell Publishing Ltd 2012 The Journal of physiology Vol.590 No.21

<P><B>Key points</B></P><P><P>Cystic fibrosis (CF) is a lethal disease characterized by low rates of epithelial Cl<SUP>−</SUP> and HCO<SUB>3</SUB><SUP>−</SUP> secretion and obstruction of the airways and gastrointestinal and reproductive organs by sticky mucus. HCO<SUB>3</SUB><SUP>−</SUP> secretion has recently been demonstrated to be necessary for mucus hydration.</P><P>The most frequent CF mutation is F508del. This mutant protein is usually degraded in the proteasome. New therapeutic strategies have been developed which deliver F508del to the plasma membrane.</P><P>Utilizing transgenic F508del mutant and cystic fibrosis transmembrane conductance regulator (CFTR) knockout mice, apical membrane expression of F508del protein was found to be associated with enhanced stimulation of intestinal HCO<SUB>3</SUB><SUP>−</SUP> secretion.</P><P>The predominant molecular mechanism for enhanced F508del HCO<SUB>3</SUB><SUP>−</SUP> stimulation appeared to be the activation of a Cl<SUP>−</SUP> recycling pathway, with Cl<SUP>−</SUP> exit via membrane‐resident F508del protein and Cl<SUP>−</SUP> entry in exchange for HCO<SUB>3</SUB><SUP>−</SUP> by apical Cl<SUP>−</SUP>/HCO<SUB>3</SUB><SUP>−</SUP> exchange. In contrast, the predominant molecular mechanism for cAMP‐activated HCO<SUB>3</SUB><SUP>−</SUP> secretion in WT intestine appears to be HCO<SUB>3</SUB><SUP>−</SUP> exit via CFTR itself.</P></P><P><B>Abstract </B> This study investigated whether expression of the common cystic fibrosis transmembrane conductance regulator (CFTR) mutant F508del in the apical membrane of enterocytes confers increased bicarbonate secretory capacity on the intestinal epithelium of F508del mutant mice compared to that of CFTR knockout (KO) mice. CFTR KO mice, F508del mutant mice (F508del) and wild‐type (WT) littermates were bred on the FVB/N background. F508del isolated brush border membrane (BBM) contained approximately 5–10% fully glycosylated band C protein compared to WT BBM. Similarly, the forskolin (FSK)‐induced, CFTR‐dependent short‐circuit current (Δ<I>I</I><SUB>sc</SUB>) of F508del mucosa was approximately 5–10% of WT, whereas the HCO<SUB>3</SUB><SUP>−</SUP> secretory response (<IMG src='/wiley-blackwell_img/equation/TJP_5291_mu1.gif' alt ='inline image'/>) was almost half that of WT in both duodenum and mid‐colon studied <I>in vitro</I> and <I>in vivo.</I> While WT intestine retained full FSK‐induced <IMG src='/wiley-blackwell_img/equation/TJP_5291_mu2.gif' alt ='inline image'/> in the absence of luminal Cl<SUP>−</SUP>, the markedly higher <IMG src='/wiley-blackwell_img/equation/TJP_5291_mu3.gif' alt ='inline image'/> than Δ<I>I</I><SUB>sc</SUB> in F508del intestine was dependent on the presence of luminal Cl<SUP>−</SUP>, and was blocked by CFTR inhibitors. The Ste20‐related proline–alanine‐rich kinases (SPAK/OSR1), which are downstream of the with‐no‐lysine (K) protein kinases (WNK), were rapidly phosphorylated by FSK in WT and F508del, but significantly more slowly in CFTR KO intestine. In conclusion, the data demonstrate that low levels of F508del membrane expression in the intestine of F508del mice significantly increased FSK‐induced HCO<SUB>3</SUB><SUP>−</SUP> secretion mediated by Cl<SUP>−</SUP>/HCO<SUB>3</SUB><SUP>−</SUP> exchange. However, in WT mucosa FSK elicited strong SPAK/OSR1 phosphorylation and Cl<SUP>−</SUP>‐independent HCO<SUB>3</SUB><SUP>−</SUP> efflux. This suggests that therapeutic strategies which deliver F508del to the apical membrane have the potential to significantly enhance epithelial HCO<SUB>3</SUB><SUP>−</SUP> secretion.</P>

Differential diagnosis of plantar wart from corn, callus and healed wart with the aid of dermoscopy

Bae, J.M.,Kang, H.,Kim, H.O.,Park, Y.M. Blackwell Publishing Ltd 2009 British journal of dermatology Vol.160 No.1

Over-expression of <i>OsIRT1</i> leads to increased iron and zinc accumulations in rice

LEE, SICHUL,AN, GYNHEUNG Blackwell Publishing Ltd 2009 Plant, cell and environment Vol.32 No.4

<P>ABSTRACT</P><P>Uptake and translocation of micronutrients are essential for plant growth. These micronutrients are also important food components. We generated transgenic rice plants over-expressing <I>OsIRT1</I> to evaluate its functional roles in metal homeostasis. Those plants showed enhanced tolerance to iron deficiency at the seedling stage. In paddy fields, this over-expression caused plant architecture to be altered. In addition, those plants were sensitive to excess Zn and Cd, indicating that OsIRT1 also transports those metals. As expected, iron and zinc contents were elevated in the shoots, roots and mature seeds of over-expressing plants. This demonstrates that <I>OsIRT1</I> can be used for enhancing micronutrient levels in rice grains.</P>

Quantitation of whole blood Epstein-Barr virus DNA is useful for assessing treatment response in patients with non-Hodgkin’s lymphoma

JO, S. A.,HWANG, S.-H.,KIM, S. Y.,SHIN, H.-J.,CHUNG, J. S.,SOL, M. Y.,CHANG, C. L.,LEE, E. Y. Blackwell Publishing Ltd 2010 INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY Vol.32 No.1

<P>Summary</P><P>Introduction. </P><P>Epstein-Barr virus (EBV) is a well-known tumorigenic virus and is associated with lymphoproliferative disorders. Quantitations of EBV viral loads in plasma and peripheral blood mononuclear cells have been reported to be useful biomarkers for monitoring Hodgkin’s lymphoma and EBV-associated non-Hodgkin lymphoma (NHL).</P><P>Methods. </P><P>In the present study, whole blood specimens were used to determine quantitatively EBV viral loads, which were then compared with clinical data. Using real-time quantitative polymerase chain reaction (RQ-PCR), EBV-DNA was monitored in whole blood samples from patients with NHL (<I>n</I> = 61) at the time of diagnosis, relapse, and follow-up.</P><P>Results. </P><P>A statistically significant correlation was observed between positive EBV viral load and extranodal involvement in diffuse large B-cell lymphoma at the time of diagnosis or relapse (<I>n</I> = 29, <I>P </I>=<I> </I>0.009). In patients who were serially checked for EBV-DNA levels (<I>n</I> = 16), viral load was found to fall to undetectable levels during complete remission. On the contrary, progressive disease and relapse were found to be associated with sustained or elevated EBV-DNA levels. </P><P>Conclusion. </P><P>These results suggest that whole blood EBV-DNA quantitation might be of value as a convenient biomarker for therapeutic responsiveness of NHL.</P>

Periodontal wound healing/regeneration following implantation of recombinant human growth/differentiation factor-5 (rhGDF-5) in an absorbable collagen sponge carrier into one-wall intrabony defects in dogs: a dose-range study

Kim, Tae-Gyun,Wikesjö,, Ulf M. E.,Cho, Kyoo-Sung,Chai, Jung-Kiu,Pippig, Susanne D.,Siedler, Michael,Kim, Chong-Kwan Blackwell Publishing Ltd 2009 Journal of Clinical Periodontology Vol.36 No.7

<P>Abstract</P><P>Aim</P><P>Recombinant human growth/differentiation factor-5 (rhGDF-5) is being evaluated as a candidate therapy in support of periodontal regeneration. The objective of this study was to evaluate cementum and alveolar bone formation, and aberrant healing events following surgical implantation of rhGDF-5 in an absorbable collagen sponge (ACS) carrier using an established periodontal defect model.</P><P>Materials and Methods</P><P>Bilateral 4 × 5 mm (width × depth), one-wall, critical-size, intrabony periodontal defects were surgically created at the mandibular second and fourth pre-molar teeth in 15 Beagle dogs. Five animals received 1 <I>μ</I>g/defect and five animals 20 <I>μ</I>g/defect rhGDF-5 in unilateral defect sites. Contralateral sites received treatments reported elsewhere. Five animals received rhGDF-5/ACS with 0 (buffer control) and 100 <I>μ</I>g/defect rhGDF-5 in contralateral defect sites. The animals were euthanized at 8 weeks post-surgery for histologic and histometric evaluation.</P><P>Results</P><P>Surgical implantation of rhGDF-5 stimulated significant periodontal regeneration. Cementum formation was significantly enhanced in sites implanted with rhGDF-5 (1 and 100 <I>μ</I>g) compared with control (<I>p</I><0.05). Similarly, bone formation height was significantly greater in sites receiving rhGDF-5 (1 and 100 <I>μ</I>g) compared with control (<I>p</I><0.05). There were no significant or remarkable differences in bone and cementum formation within the selected dose interval (1, 20 and 100 <I>μ</I>g rhGDF-5). None of the control or the rhGDF-5 sites exhibited root resorption, ankylosis, or other aberrant tissue reactions.</P><P>Conclusion</P><P>Surgical implantation of rhGDF-5/ACS may be used safely to support periodontal wound healing/regeneration in intrabony periodontal defects without complications.</P>

Partial replacement of NaCl by KCl in salted mackerel (<i>Scomber japonicus</i>) fillet products: effect on sensory acceptance and lipid oxidation

Park, Jae N.,Hwang, Keum T.,Kim, Sook B.,Kim, Sung Z. Blackwell Publishing Ltd 2009 International journal of food science & technology Vol.44 No.8

<P>Summary</P><P>Mackerel fillets were salted with NaCl and/or KCl to determine the most acceptable level by sensory evaluation. Additionally, the effects of ascorbic acid, vacuum packaging, and cold storages on lipid oxidation were determined for the salted mackerel fillets. Appropriate level of NaCl was ≤2%. Fifty percent replacement of NaCl by KCl reduced NaCl level with minimal impact on sensory quality. The higher the level of ascorbic acid (0–0.5%, weight basis), the higher the antioxidant effect observed with thiobarbituric acid value and peroxide value. There was no significant difference in sourness (&agr; = 0.05) between the salted mackerel samples treated with and without ascorbic acid (0.25%). Vacuum packaging and storage at −18 °C along with ascorbic acid was most effective in retarding lipid oxidation in the salted mackerel. Vacuum-packaged sample with ascorbic acid stored at 2 °C was least oxidised, followed by vacuum packaging without ascorbic acid and then ascorbic acid without vacuum.</P>

A novel hemoglobin variant beta135(H13) Ala > Asp identified in an asymptomatic Korean family by direct sequencing: suggesting a new insight into Hb Beckman mutation

KIM, S. Y.,KIM, G. Y. J.,JO, S. A.,LEE, E. H.,CHO, E. H.,HWANG, S. H.,LEE, E. Y. Blackwell Publishing Ltd 2010 INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY Vol.32 No.1

<P>Summary</P><P>This article describes the clinical observation of a novel hemoglobin (Hb) variant found during the course of routine blood testing on a 61-year-old subject. The Hb variant was observed during HbA1c testing by ion-exchange high-performance liquid chromatography. Alkaline electrophoresis and DNA sequencing confirmed the presence of a new Hb variant, <I>HBB</I>:c.407C > A (p.Ala136Asp). This mutation has been reported to induce Hb Beckman variant in the Globin Gene Server. However, it was different from the only experimental report for Hb Beckman by Rahbar, Lee & Asmeron (p.Ala136Glu; Hb Beckman alpha2 beta2 135(H13) ala-to-glu: a new unstable variant and reduced oxygen affinity. <I>Blood</I> 78, 204a). And our case was asymptomatic with normal lab findings, while Rahbar <I>et al.</I>’s case showed the clinical manifestations of chronic anemia. This would be a report for a novel Hb variant suggesting new insight of Hb Beckman variant. This would be a report of a novel Hb variant suggesting new insights into Hb Beckman variant.</P>